People don't stop growing at 18, studies show that people continue growing well into their twenties at a much slower rate but they do grow. Your pituitary gland not automatically magically turn off at 18.
Children can be much taller then their parents based on nutrition alone. Most foods are enriched now. Studies have even shown that even Pygmies a notoriously small people will grow far more then their parents with proper nutrition. The average human height has increased over the centuries due to nutrition and availability of food alone.
As for Baryta Carbonica, it is technically a poison. It can increase irritation in the abdominal organs causing peristaltic action of the bowels. It can in rare cases cause paralysis in cardiac muscles. It has similar properties to Belladonna. It can be useful in cases where people have severe tremors, however it should only be used under the full guidance and care of a real MD.
If you're going to give medical advice with your very minor training, you should do your research and you should also have a disclaimer that fully states that you are not a medical doctor nor have you had the training to give any medical advice and in fact giving medical advice with your lack of knowledge and education is indeed an immoral act and you are most likely shrinking right now.

Yes - however biscuits and pancakes are made from almost the same recipe - it was a family joke when I was 8 years old or so when people would tease me.- but I took the advice and am just under 6 ft 4 in tall - so who knows.

Nutrition does play some part - I think I saw that the average height of people in Japan jumped 3 or 4 inches in a generation or two following World War II when they had a better balanced diet.

Yes it is a good alternative of poison when you take the whole bottle at once. Cause it (and many or almost all the homeopathic) medicines contain 90% alcohol. And taking concentrated alcohol (90%alcohol 10%water) (when Methylated) is more dangerous than poison.
OMG censor my comment please :D
But taking homeopathic medicines in the form of solid has no negative affect on you.(there's alcohol in less than 1%)
I don't think any pill can extend your height more than 2-3 inches.
All the medicines we see in the ads have rich side effects. Cause most of them contain steroids or vitamins. There's a logic Our body makes steroid by itself and taking them from outside causes disturbances in the body. I think exercise and taking good food makes you tall. I'll tell you tomorrow after asking it from medical specialist of my store.
Is whey protein good to take? Is there any side effect of it?

Genetics play only 25% role in it. My father was only 5 6 and my mother is just 5 4 and my brother is 6 1...........

I have five brothers all over 6', my mum was 5' 2 dad was 5' 6, when I was 18 I was 5' 7, when I was 22 I was 5' 9 as I still am now and do you know why, I found another 2" in the pocket of my old genes... x

@hnsaifi. It was a quote from iphonist's post above. Admittedly it's posted wrong and my comment is also in the quotation box. But to admit to forgetting maths when supposedly studying medicine is to my mind, appalling.